1. Field of the Invention
The invention relates to cleaning, in particular, to scraping machines.
2. Description of the Prior Art
Dust from coke built up on flue walls of furnace pits is a major source of in-plant air pollution in carbon product baking foundries. Due to the present national concern about air pollution, the U.S. Congress enacted the Occupational Safety and Health Act (hereinafter OSHA), effective April, 1971. Thereunder, regulations have been promulgated to govern the permissible dust exposure for employees inside a plant.
Before the present invention was conceived and reduced to practice, coke built up on flue walls of open-top furnace pits in carbon product baking foundries was removed by hand implements, such as scrapers, chisels, etc., operated by a plurality of workers, usually six, who would climb down into a cooled-off furnace pit in order to manually chip away and laboriously clean the entire surface of the flue walls. Such an operation ordinarily lasted a full eight-hour work day. Such labor was tedious, boring, and dangerous to the workers' health because of their constant inhalation of the coke dust. The use of protective mouth and nose respirators helped alleviate the hazards somewhat but the apparatuses were bulky and uncomfortable for the workers to wear.
Many attempts have been made to develop devices for cleaning simultaneously the opposed walls of other types of furnace pits safely and efficiently. Exemplary prior art machines for cleaning the inside of large containers are shown and described in U.S. Pat. Nos. 3,471,888, 3,992,745, and 3,996,637. However, none of these apparatuses is suitable for cleaning furnace flue walls made of refractory brick.
Therefore, it is still a problem in the cleaning art to manufacture a safe and effective device for cleaning simultaneously opposed walls of an open-top furnace pit in a carbon product baking foundry.